WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] [PATCH] linux/balloon: don't allow ballooningdowna domai

To: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] linux/balloon: don't allow ballooningdowna domain below a reasonable limit
From: Alan Cox <alan@xxxxxxxxxxxxxxxxxxx>
Date: Fri, 2 May 2008 00:03:10 +0100
Cc: "dan.magenheimer@xxxxxxxxxx" <dan.magenheimer@xxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>, Ky Srinivasan <KSrinivasan@xxxxxxxxxx>, Jan Beulich <jbeulich@xxxxxxxxxx>, KurtGarloff <garloff@xxxxxxx>
Delivery-date: Thu, 01 May 2008 16:11:30 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <C43FF23D.18160%keir.fraser@xxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Organization: Red Hat UK Cyf., Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, Y Deyrnas Gyfunol. Cofrestrwyd yng Nghymru a Lloegr o'r rhif cofrestru 3798903
References: <20080501105958328.00000002360@djm-pc> <C43FF23D.18160%keir.fraser@xxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
> It might be the case though that, in practice, vm_committed_space is a
> reasonable predictor for working set for some common types of workload. Many
> applications probably keep their heaps fairly warm and hence in main memory.

I am dubious. What vm_committed_space does allow you to do however if you
watch it in Xen is to actually ensure you never balloon out a virtual
machine to the point you make it start killing stuff off.

There are better ways to measure memory pressure - sizes of the various
active and inactive lists etc. OLPC has code for this and a proposed
memory pressure notifier feature that they use to allow user space apps
to cleanup.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

<Prev in Thread] Current Thread [Next in Thread>